1. Field of the Invention
The present invention is directed to shale shakers with cartridge screen assemblies.
2. Description of Related Art
Vibratory separators are used in a wide variety of industries to separate materials such as liquids from solids or solids from solids. Typically such separators have a basket or other screen holding or mounting apparatus mounted in or over a receiving receptacle or tank and vibrating apparatus for vibrating the basket. One or more screens is mounted in the basket. Material to be treated is introduced to the screen(s) either by flowing it directly onto the screen(s) or by flowing it into a container, tank, or “possum belly” from which it then flows to the screen(s). Also in some multi-screen apparatuses material flows generally horizontally or uphill from one screen to another and, in certain systems, from an upper screen onto a lower screen.
FIG. 1 illustrates an apparatus according to the prior art, in which the debris laden mud 1 flows downwardly through a vibrating flat screen 2 to filter out the debris. The screen 2 is vibrated by vibrating the whole body of the apparatus using motors 3 with eccentric weights, for example. The cleaned mud exits the apparatus and then generally is ready for re-use. Debris that does not pass through the screen is caught on the screen and is carried by the direction and amplitude of the screen vibration upwardly towards an exit 4. Corrugated shaped screens have been used in the industry. In certain prior art screens the mud passes either vertically down through the screen, as is the case with the flat screens, or has a downward component to the flow, as is the case with certain three-dimensional screens. Arrangements have been proposed where the angle of the screen is increased and may be vertical in parts.
Examples of the general configuration of filter are disclosed in U.S. Pat. No. 4,459,207, WO-A-02 43 832 and WO-A-03 028 907.